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- J. G. YEMEN.

DENTAL PLATE.

No. 250,320. Patented NOV. 29,1881.

- WITNESSES V n 311% .ttornq UNITED STATES PATENT OFFICE.

JOHN G. YEMEN, OF STRATFORD, ONTARIO, CANADA.

DENTAL PLATE.

SPECIFICATION forming part of Letters Patent No. 250,320, dated November 29, 1881.

Application filed March 7, 1881. (No model.)

To all whom it may concern Be it known that 1, JOHN G. YEMEN, of Stratford, in the Province of Ontario and Dominion of Canada, have invented certain new and useful ImprovementsinDentalPlates; and 1 do hereby declare that the following is afull, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification, and in which Figure l is a perspective view of my improved dental plate or denture, and Fig. 2 is a cross-section of the same.

Similar letters of reference indicate corresponding parts in both the figures.

My invention has relation to that class of dental plates or dentures which are provided with a rubber valve for their better attachment to the roof of the mouth. In this class of plates as heretofore made the valve has been made of a separate piece of rubber of a cup shape, and attached by means of a metallic rivet to the roof of the plate. This construction is objectionable for two reasons. In the first place, by riveting the valve its edges become turned up, so as to irritate the mouth; and, secondly, the metallic rivet not only detracts from the appearance of the plate, but is apt to cause inflammation of the mouth.

It is the object of my improvement to overcome these drawbacks by making the plate and its valve in one piece without any rivet, by which I am enabled to make the valve much thinner than otherwise, besides making the body of the plate thinner, and thus more agreeable to wear.

In theaccompanying drawings, Ais theplate, and B the flexible valve. The latter, as will be seen by reference to Fig. 2, forms one integral part of the plate, and has a flat annular rim, 5, surrounding its central depression or cavity, a. The valve-disk is so thin that it, when the plate is in use, will lie flat in the cavity 0 in the roof of the plate, and even or flush with the edge of said cavity, by which allirritation of the root of the mouth is avoided.

The soft cup-shaped valve B, with its flat annular rim 1) encircling its central cavity or depression, a, is made in the process of vulcanization of the palate-plate A, and forms, as stated above, an integral part thereof, so that the plate in its entirety, or as a whole, is composed of the hard-rubber part A and soft-rubber part B, both in one piece.

I claim as my improvement and desire to secure by Letters Patent of the United States- A dental plate composed of the hard-rubber palate-plate A, recessed at c, and soft-rubber valve B, having a flat annular rim, 1), encircling its central cup-shaped depression, a, the parts A B being integral or in one piece, as set forth.

In testimony that I claim the foregoing as my own I have hereto affixed my signaturein presence of two witnesses.

JOHN GUTHRIE YEMEN.

Witnesses CHARLES MAIN BYGRAVE LAWRENCE, WM. LAWRENCE. 

